复制启动蛋白调节了Bacillus subtilis的一个发育检查点
W F Burkholder1, I Kurtser, A D Grossman
1Department of Biology, Massachusetts Institute of Technology, Building 68, Room 530, Cambridge, MA 02139, USA.
Cell
|February 24, 2001
概括
一个涉及sda的新发现的信号通路,当DNA复制启动有缺陷时,可以防止Bacillus subtilis Sporulation. 这一检查点确保细胞资源在复制压力期间不会被浪费在分泌上.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 在 Bacillus subtilis 中,胞形成是一个复杂的过程,对生存至关重要.
- 复制的启动对于细胞分裂至关重要,并且必须与其他细胞过程协调.
- 缺陷的DNA复制启动通常会抑制分泌的发生.
研究的目的:
- 为了确定将受损的复制启动与化抑制联系起来的分子机制.
- 阐明sda基因在这个调节途径中的作用.
- 了解 Bacillus subtilis 如何在复制压力下防止分泌.
主要方法:
- 隔离和特征自发突变允许在复制启动突变体中分泌.
- 基因分析包括基因删除和过度表达.
- 使用纯化的Sda蛋白进行生物化学测试.
主要成果:
- 在一个小的开放式读取框架中的突变,sda,在复制启动突变者中恢复了分泌.
- 发现Sda在复制突变体中过度表达,并由DnaA调节.
- Sda直接抑制了Spo0A激活所必需的胺基酶,从而阻断了胞形成.
结论:
- 在DNA复制受损时,DnaA介导的sda控制作为一个检查点来抑制分泌.
- 这种机制可以防止在复制应激下浪费地启动化.
- 该sda途径提供了DNA复制状态和决定化之间的关键联系.
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